Guide blade mounting means for steam or gas turbines

ABSTRACT

A mounting means for the guide blades of a steam or gas turbine comprising an inner ring to which each blade is axially locked by means of crossed bars which respectively extend across the ring and through a shroud which is secured to an end of the blade. The crossbars extend at an angle with respect to one another and by the selection of crossed bars having different degrees of angularity, replaced blades can be set in various angular positions to meet different requirements.

United States Patent Inventor Ragnar Nlls Anders Torstenlelt Flnspong. Sweden Appl. No. 47,434

Filed June 18, I970 Patented Nov. 9, 1971 Assignee Stal-Laval Turbln AB Flnspong, Sweden Priority July 8, 1969 Sweden 9656/69 GUIDE BLADE MOUNTING MEANS FOR STEAM OR GAS TURBINES 3 Claims, 4 Drawing Figs.

US. Cl 415/189. 415/21 1.415/217 Int. Cl F041 5/48. I F04b 49/00 Field of Search 415/186,

[56] Relerences Cited UNITED STATES PATENTS 2,439,933 4/1948 Jenkins 1,119,713 12/1914 Moss 1,341,859 6/1920 Moody 1.673.151 6/1928 Lindcrnann FOREIGN PATENTS 976,790 11/1950 France ,4 307,832 10/1929 Great Britain... 691,380 5/1953 Great Britain Primary Examiner-Henry F. Raduazo Auorney- Munson & Fiddler ABSTRACT: A mounting means for the guide blades of a steam or gas turbine comprising an inner ring to which each blade is axially locked by means of crossed bars which respectively extend across the ring and through a shroud which is secured to an end of the blade. The crossbars extend at an angle with respect to one another and by the selection of crossed bars having different degrees of angularity, replaced blades can be set in various angular positions to meet different requirements.

PATENTEDNUV 9 ml 3.619.079

NILS ANDERS RAGNAR TORSTENI-BLT,

Inventor MUNSON & FIDDLER,

Attorneys.

GUIDE BLADE MOUNTING MEANS FOR STEAM OR GAS TURBINES BACKGROUND OF THE INVENTION In steam or gas turbines for use under high temperatures, the first-stage guide blades in particular in such devices, are easily damaged by the high temperature. Individual guide blades in these turbines must-therefore be replaced at relatively frequent intervals. Up to the present time, this has proved to be a time-consuming and costly procedure, since for the purpose of blade replacement the turbine had to be partly dismantled. The present invention has for one of its objects, the provision of an arrangement for the mounting of guide blades which is so arranged that the guide blades may be easily removed and replaced and set at the required angle of incidence in the guide blade ring.

DESCRIPTION In the accompanying drawing, wherein an illustrative embodiment of the invention is disclosed,

FIG. I shows a guide blade ring in axial cross section and in accordance with the invention;

FIG. 2 shows the same ring in a radial cross section, the view being taken along the line ll-II in FIG. 1;

FIG. 3 is a cross-sectional view taken along the line IIllII in FIG. I, and

FIG. 4 is a perspective view of the crossed keys.

In the drawing 1 indicates a guide blade mounted in a guide blade ring through which a working medium flows in the direction of the arrows 2. Each guide blade 1 is mounted between shrouds 3 and 4. As shown in FIG. 3, the arcuate or circular edge 5 of the shroud 4 is in contact on the downstream side with the arcuate or circular edge 6 of the fixed inner ring 7 to which the shroud 4 and hence the guide blade 1 is locked radially by the edge 8 of the shroud 4 engaging in a groove 9 in the edge 6.

In a similar manner, an arcuate or circular edge of the shroud 3 is in contact with an arcuate or circular edge 10 of a fixed outer ring 11. Between this ring 11 and the shroud 3 there is a clearance which enables the guide blades to expand freely during the operation of the turbine.

The guide blade 1 is locked axially to the inner ring 7 by means of cross keys such as the bars shown in FIG. 4, such bars consisting of a bar 12 engaging in a peripheral groove 13 in the ring 7, and a bar 14 which extends across and is fixed to the bar 12 and engages in an axial groove 15 formed in the shroud 4. The bar 14 is somewhat longer than the shroud 4, the protruding part of the bar 14 being peened over against the upstream side of the shroud 4 to thereby lock the guide blade I to the inner ring 7. When replacing a guide blade, this peened section is removed, the blade is then extracted and is replaced by a new one.

By having the crossed keys arranged at different angles between the bars 12 and 14, it is possible to change the angles and flow areas of the guide blades, in order to increase the efficiency. The circular edges 5, 9 and I0 enable this angular setting to be made.

From the foregoing, it will be apparent that by the removal of the peened portion of the bar 14, the bars 12 and M can be removed and the blade 1 taken out and replaced by a new blade. By having the bars 12 and 14 disposed at different angles with respect to the blade, the angularity of the blade in its mounting will be determined.

What I claim is:

I. An arrangement for mounting guide blades for turbines comprising, a guide blade, a ring to which the guide blade is locked, the ring having a peripheral groove, said groove being transverse in relation to the turbine shaft, a crossbar extending through said groove, a shroud at one end of the guide blade, said shroud having a groove disposed at an angle to the groove in the ring, a crossbar extending through the groove in the shroud, the ring having an edge portion, the last-mentioned crossbar having a peened-over end, the shroud being axially maintained in a space between said edge portion and said peened-over end.

2. An arrangement according to claim I, wherein the shroud has an arcuate edge in contact with the edge portion of the ring; the ring having a complementary arcuate curvature to enable it to be possible to alter the setting angles of the guide blades by the replacement of the cross keys with keys of different angles between the crossbars.

3. An arrangement for mounting guide blades of turbines comprising, a mounting ring having a groove, a blade having a shroud at one end, said shroud being provided with a groove at an angle to the groove in the ring, a pair of bars in crossed and united relationship, said bars respectively fitting in the grooves, one of the bars having a peened end preventing its removal from its groove.

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1. An arrangement for mounting guide blades for turbines comprising, a guide blade, a ring to which the guide blade is locked, the ring having a peripheral groove, said groove being transverse in relation to the turbine shaft, a crossbar extending through said groove, a shroud at one end of the guide blade, said shroud having a groove disposed at an angle to the groove in the ring, a crossbar extending through the groove in the shroud, the ring having an edge portion, the last-mentioned crossbar having a peened-over end, the shroud being axially maintained in a space between said edge portion and said peened-over end.
 2. An arrangement according to claim 1, wherein the shroud has an arcuate edge in contact with the edge portion of the ring; the ring having a complementary arcuate curvature to enable it to be possible to alter the setting angles of the guide blades by the replacement of the cross keys with keys of different angles between the crossbars.
 3. An arrangement for mounting guide blades of turbines comprising, a mounting ring having a groove, a blade having a shroud at one end, said shroud being provided with a groove at an angle to the groove in the ring, a pair of bars in crossed and united relationship, said bars respectively fitting in the grooves, one of the bars having a peened end preventing its removal from its groove. 